Ram Swaroop Meena

Potassium Uptake by Crops as Well as Microorganisms

Potassium (K) is one of the essential major plant nutrients. Its importance in agriculture has increased with intensive agriculture as well as deficiency occurring in crop plants. Global population is increasing at a quantum rate, which pushes the targeted yield to higher levels for mitigating the food demand of hungry mouths. Production of more food material from limited land is a challenge for the researcher and it aggravates nutrient deficiency, due to more uptake of plant nutrients, especially K, by high-yielding crop varieties. Among plant nutrients, deficiency of K limits the crop growth and reduces the crop yield. The source of K is native or via various replenishment paths, i.e. crop residue, microbial biomass and a range of waste materials. Researchers mentioning the wide gap between the addition of K and removal during crop production are highlighting the challenge to maintain a sustainable crop yield. The nutrient balance in the soil system is also affected by the quantity of nutrient that is taken up, raising nutrient storage in the soil–plant–microbe system, and how much is recycled by crop residues. The use of potassium-solubilizing microorganisms (KSMs) can increase the K level in the soil solution and ultimately increase plant growth and development. The main mechanisms of KSMs are acidolysis, chelation, exchange reactions, complexolysis and organic acid production in the soil. K fertilizers cost much more than other fertilizers, so use of KSMs in agricultural crop production can be a sustainable option for enhancing in situ K availability from the fixed sink of agricultural soils.

Potassium Solubilizing Microorganisms for Sustainable Agriculture

The potassium solubilizing microorganisms (KSMs) are a rhizospheric microorganism which solubilizes the insoluble potassium (K) to soluble forms of K for plant growth and yield. K-solubilization is carried out by a large number of saprophytic bacteria (Bacillus mucilaginosus, B. edaphicus, B. circulans, Acidothiobacillus ferrooxidans, Paenibacillus spp.) and fungal strains (Aspergillus spp. and Aspergillus terreus). Major amounts of K containing minerals (muscovite, orthoclase, biotite, feldspar, illite, mica) are present in the soil as a fixed form which is not directly taken up by the plant. Nowadays most of the farmers use injudicious application of chemical fertilizers for achieving maximum productivity. However, the KSMs are most important microorganisms for solubilizing fixed form of K in soil system. The KSMs are an indigenous rhizospheric microorganism which show effective interaction between soil-plant systems. The main mechanism of KSMs is acidolysis, chelation, exchange reactions, complexolysis and production of organic acid. According to the literature, currently negligible use of potassium fertilizer as chemical form has been recorded in agriculture for enhancing crop yield. Most of the farmers use only nitrogen and phosphorus and not the K fertilizer due to unawareness that the problem of K deficiency occurs in rhizospheric soils. The K fertilizer is also costly as compared to other chemical fertilizers

Influence of bioinorganic combinations on yield, quality and economics of mung bean.

A field study was conducted during rainy ( kharif ) season of 2013 to find out the effect of bioinorganic nutrient combinations on yield, quality and econ omics of mungbean [ Vigna radiate (L.) Wilczek]. The twelve treatments comprised one control, three levels of in organic sources (75, 50 and 100 % NPK of recommended dose) and other eight in combination viz. 50% RDF+ Rhizobium + Phosphorus solublizing bacteri a (PSB), 50% RDF + 2.5 t/ha Vermicompost, 50% RDF+2.5 t/ha Vermicompost/ha + Rhizobium + PSB, 75% RDF+ Rhizobium + PSB, 75% RDF + 2.5 t/ha Vermicompost, 75% RDF + 2.5 t/ha Vermicompost + Rhizobium +PSB, 100%RDF+ Rhizobium + PSB and 100% RDF + 2.5 t/ha Vermi compost were laid out in randomized block design with three replications. Amongst combinations, significant improvement in plant height at harvest, yield attributes, yield, protein per cent, nutrient content and uptake were recorded with application of nut rients through 75% RDF + 2.5 t/ha vermicompost + Rhizobium + PSB as compared to other combinations, followed by treatments 100% RDF + 2.5 t/ha vermicompost and 100% RDF + Rhizobium + PSB. The highest and comparable net returns were obtained with the applic ation of

Legume Green Manuring: An Option for Soil Sustainability

Overuse of nitrogen (N) fertilizer to enhance agricultural production is threatening the environment. The concentrations of reactive forms (e.g., NOx, N2O, NO3−, NH3) of N have increased to around 120% in the atmosphere as a result of different industrial units and use of chemical fertilizers in agriculture. The scenario compels to rethink about the role of biological nitrogen fixation (BNF). Green manuring with inclusion of legumes appears to be the most feasible option. Intensive agriculture with repeated tillage, use of high-analysis fertilizers, burning of agricultural residue, and non-incorporation of biodegradable solid waste from domestic and industrial sectors into soil mass have resulted in the decline of soil organic carbon (SOC). This in turn impaired soil health, decreased soil biodiversity, and aggravated the demand for essential plant nutrients, leading to the agricultural land becoming less productive and sometimes unfit for economic cultivation. The uncontrolled use and improper management of synthetic fertilizers, especially, the nitrogenous fertilizers, emit nitrate (NO3−) causing water pollution and nitrous oxide (N2O), speeding up climate change process and oxides of N (NOx) causing air pollution. The OC and soil nitrogen have a positive correlation. It suggests that soil nitrogen level can be improved with improving levels of soil organic matter (SOM). It will also help in reducing environmental damage due to overuse of nitrogen fertilizers. Green manuring with legumes has added advantage as legumes fix atmospheric nitrogen and are easily decomposable. Legume green manuring (LGM) improves SOC, nutrient availability, physicochemical and biological properties of soil, and crop productivity. Several legumes which were used for green manuring showed high N accumulation rate, i.e., 80–100 kg ha−l in duration of 45–60 days of crop growth. Legume crop cultivation, say seed legumes in symbiotic association with Rhizobium, contributes around 10 Tg N year−1, while forage legumes (cover crops) contribute 12 Tg N year−1. Application of LGM is an important option to optimize the BNF and to ensure soil sustainability. The LGM may have a realistic and applicable potential in the area where soil properties are marginal for crop production.

Response of sowing dates and bio regulators on yield of clusterbean under current climate in alley cropping system in eastern U.P., India

The impacts on yields of cluster bean were assessed for normal (15 July) and late (30 July) sowing environments and foliar spray of thiourea (500, 1000 ppm) and salicylic acid (50, 100 ppm) at 45 and 60 days after sowing (DAS).Significantly higher yield parameters, yield, economics, protein content and nutrient uptake were recorded with foliar spray of thiourea at 500 ppm as compared to all other bio regulator sprays. Similarly, spray of salicylic acid at 100 ppm enhanced yield and other growth parameters which were statistically at par with those for thiourea 500 ppm foliar spray at 45 and 60 DAS. The data show that the foliar application of bio regulators at normal sowing date enhances seed yield of clusterbean by improving the physiological processes. The interaction effects were significant between the sowing date and bio-regulators on the seed yield. The highest seed yield of 993 and 845 kg/ha was obtained with foliar spray of thiourea at 500 ppm in normal and late sowing, respectively, while the lowest yield of 775 and 769 kg/ha was obtained for the water spray control in normal and late sowing, respectively.